﻿<!--
 * @Description: 
 * @Version: 1.0.0
 * @Author: Kevin.Lee
 * @Date: 2021-04-09 09:51:07
 * @LastEditors: Kevin.Lee
 * @LastEditTime: 2021-04-09 10:30:19
 * @FilePath: /maptalks.three-0.11.2/Users/lijinwen/study-p/doc/three-study/example/demo8/index10-2.html
 * Copyright (C) 2021 Kevin.Lee. All rights reserved.
-->
<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>创建RGBA数据</title>
    <!-- <script src="https://cdn.staticfile.org/jquery/3.5.1/jquery.min.js"></script> -->
    <script src="../../js/three.js"></script>
    <script src="../../js/controls/OrbitControls.js"></script>
    <style type="text/css">
        body {
            margin: 0;
            overflow: hidden;
        }
    </style>
</head>

<body>
    <script>
        /**
         * 创建场景对象Scene
         */
        var scene = new THREE.Scene();
        // var geometry = new THREE.PlaneGeometry(128, 128); //矩形平面
        var geometry = new THREE.BoxGeometry(200, 200, 200); //立方体
        /**
         * 创建纹理对象的像素数据
         */
        var width = 32; //纹理宽度
        var height = 32; //纹理高度
        var size = width * height; //像素大小
        var data = new Uint8Array(size * 4); //size*4：像素在缓冲区占用空间
        for (let i = 0; i < size * 4; i += 4) {
            // 随机设置RGB分量的值
            data[i] = 255 * Math.random()
            data[i + 1] = 255 * Math.random()
            data[i + 2] = 255 * Math.random()
            // 设置透明度分量A
            data[i + 3] = 255 * 0.5
        }
        // 创建数据文理对象   RGBA格式：THREE.RGBAFormat
        var texture = new THREE.DataTexture(data, width, height, THREE.RGBAFormat);
        texture.needsUpdate = true; //纹理更新
        //打印纹理对象的image属性
        console.log(texture.image);

        var material = new THREE.MeshPhongMaterial({
            map: texture, // 设置纹理贴图
            transparent: true, //允许透明设置
        }); //材质对象Material
        var mesh = new THREE.Mesh(geometry, material); //网格模型对象Mesh
        scene.add(mesh); //网格模型添加到场景中
        /**
         * 光源设置
         */
        //点光源
        var point = new THREE.PointLight(0xffffff);
        point.position.set(400, 200, 300); //点光源位置
        scene.add(point); //点光源添加到场景中
        //环境光
        var ambient = new THREE.AmbientLight(0xaaaaaa);
        scene.add(ambient);
        /**
         * 相机设置
         */
        var width = window.innerWidth; //窗口宽度
        var height = window.innerHeight; //窗口高度
        var k = width / height; //窗口宽高比
        var s = 150; //三维场景显示范围控制系数，系数越大，显示的范围越大
        //创建相机对象
        var camera = new THREE.OrthographicCamera(-s * k, s * k, s, -s, 1, 1000);
        camera.position.set(200, 300, 200); //设置相机位置
        // camera.position.set(0, 0, 200); //设置相机位置
        camera.lookAt(scene.position); //设置相机方向(指向的场景对象)
        /**
         * 创建渲染器对象
         */
        var renderer = new THREE.WebGLRenderer();
        renderer.setSize(width, height); //设置渲染区域尺寸
        renderer.setClearColor(0xb9d3ff, 1); //设置背景颜色
        document.body.appendChild(renderer.domElement); //body元素中插入canvas对象

        // 渲染函数
        function render() {
            renderer.render(scene, camera); //执行渲染操作
            requestAnimationFrame(render); //请求再次执行渲染函数render，渲染下一帧
        }
        render();
        //创建控件对象  相机对象camera作为参数   控件可以监听鼠标的变化，改变相机对象的属性
        var controls = new THREE.OrbitControls(camera, renderer.domElement);
        //监听鼠标事件，触发渲染函数，更新canvas画布渲染效果
        // controls.addEventListener('change', render);
    </script>
</body>

</html>